The present invention relates in general to a stringed musical instrument, and preferably an instrument such as a guitar. More particularly, this invention pertains to a musical instrument that has improved means for sustaining the characteristic sound of the instrument.
In the course of a prior art investigation, the following U.S. Patents have been uncovered: Nos. 472,019; 1,002,036; 2,401,372; 3,185,755; 3,524,375; 3,742,113; 4,075,921; and Canadian Pat. No. 461,969. The prior art, as exemplified in, for example the Cohen U.S. Pat. No. 3,742,113 shows a feedback arrangement, that provides a sustenance action. However, this patent and many similar prior art devices cause distortion of the musical sound using such feedback techniques. On the other hand, one of the purposes of the present invention is to provide, in one embodiment disclosed herein, a form of feedback that enhances the natural tone of the sound.
The plane of vibration of a plucked string of an instrument naturally precesses at a relatively slow frequency effecting the tone quality of the instrument. With the use of a conventional drive arrangement such as shown in the Cohen patent the plane of vibration is essentially restricted to a single plane thus effecting the tone quality of the instrument. Accordingly, one object of the present invention in accordance with one version thereof is to provide sustenance means for maintaining string vibration to provide this longitudinal displacement of the string causing natural precession of the plane of vibration of the string.
In the prior art construction such as in the Cohen patent, the feedback arrangement is somewhat complex and requires separate mounting for the pickup and drivers. Also, there is a substantial distance between the pickup and drivers and apparently in this construction the electronics must also be supported separately from the other portions of the feedback loop. To overcome some of these drawbacks of the prior art construction, in accordance with the invention there is provided a common support for the pickup driver and associate electronics, which support also includes means defining a bridge or tail piece from which the strings are mounted. Furthermore, in accordance with the invention there is associated with the driver, a shield means which also provides an improved operation.